Do ball sector valves with double eccentricity allows process pressure to open the valve 1

[KevinNZ]

Hi all

Do ball sector valves with double eccentricity (eccentric rotary plug control valve) allows process pressure to assist with opening the valve?

Seems to me the shaft offset puts a moment on the ball from the shut in pressure. None of the valve vendors sites I looked at mention this.

 

[GBTorpenhow]

Yes. From Fisher V500 bulletin:

https://www.emerson.com/documents/a...isher-v500-rotary-control-valve-en-122382.pdf